Half to adolph mack



(No Model.)

' T. THRELPALL.

SYR'INGE.

No. 368,627.. Patented Aug. 23, 1887.

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Men STATES THOMAS THRELFALL, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OFONE- HALF TO ADOLPI-I MACK, OF SAME PLACE.

SYRINGE.

SPECIFICATION forming part of Letters Patent No. 368,627, dated August23, 1887. 7

Application filed December 3, 1886. Serial No. 220.622. (No model.)

To aZZ whom it may concern:

Be it known that I, THOMAS THRELFALL, residing at San Francisco, in thecounty of San Francisco and State of California, have invented a new anduseful Improvement in Syringes, of which the following is aspecification.

My invention relates especially to that class of syringes employed forinjecting medical compounds for treating diseases.

To attain this end my invention consists, essentially, in two barrelsand one piston or a syringe proper contained within a surroundingcylinder and of peculiar construction, as set forth in the claim.

The lower end of the inner cylinder or syringe is pierced for a valveand the valve packed with an elastic packing, the tip of the syringepassing through it, in which position it is held by a cap screwed to thelower end of the outer cylinder, the tip of the syringe also passingthrough the screw-cap, which latter forms a seat for the elasticpacking. A screw-thread is formed upon the upper end of the outercylinder, which receives a screwcap connected to the syringe proper nearthe upper end thereof, the construction and arrangement of the partsbeing such that the fluid is drawn into the syringe and then forced intothe outer cylinder, to be forced back into the syringe in suitablevolume when required for use, the outer cylinder acting in the capacityof a reservoir or bottle.

In the drawings forming a part of this specification, Figure l is alongitudinal section through my improved bottle-syringe. Fig. 2 is anelevation of syringe with part in section.

Let A represent the syringe proper, constructed in the ordinary mannerwith barrel, piston, tip, and screw-cap.

The lower end of the barrel of the syringe is pierced with a hole, b,opposed to which is.

an elastic packing, a, the latter having its seat in a screw-capconnected to the lower end of an'outer cylinder, with the tip of thesyringe extending through the cap and packbarrel of the syringe and endof the outer cylinder, while the latter, or screw-cap g, is screwed tothe threaded lower end of the outer cylinder, leaving a chamber ofsufficient capacity between it and the barrel of the syringe.

In practice the liquid or fluid is drawn into the syringe or innerbarrel through the tip, in the usual manner, by raising the piston, andthe syringe-barrel drawn upward or backward by unscrewing the screw-capse f, which releases the elastic packing from the holes or valve 5. Thenby a downward stroke of the piston the fluid is forced through the holesor valve 1) into the outer cylinder, (1, after which the caps e f arescrewed back to their seat. Thus the fluid is drawn into the syringe andforced out and held in the chamber or cylinder cl with the piston of thesyringe down its fullstroke.

In order to draw a sufficient quantity of fluid from the cylinder orreservoir back into the syringe for ejection, the finger is again placedover the tip of the syringe and the caps e f again unscrewed and thepiston drawn back, which draws back by suction into the syringe thedesired quantity of fluid, to be forced out in the usual way when thefinger is removed from the tip and the caps e f turned back again upontheir seat upon the end of the cylinder.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, 1s

The combination of the ordinarily-constructed syringe A, having in itslower end a hole, I), the outer cylinder, (1, surrounding the syringe A,and the screw-caps e, f, and g, for holding the outer cylinder inposition, said cap e being movable on the screw-threaded barrel A, saidcap f being movable on barrel A and cylinder d, and said cap 9 beingscrewed to the threaded lower end of cylinder d and forming a seat foran elastic packing, 0, all arranged and operated substantially asdescribed.

In testimony that I claim the foregoing I have hereunto set my hand andseal.

THOMAS TI-IBELFALL. [L. s]

Witnesses:

O. W. M. SMITH, CHAS. E. KELLY.

